Right-click the cell that contains the field [Qty] , and click Add Total. This adds a sum of the quantity for each order to the totals row. In the empty cell to the left of Sum[Qty] , type the label  Order Total . You can add a background color to the totals row. Select the two sum cells and the label cell.
Ladder logic is the first in a series exploring different software programming methods how to choose the most appropriate model of computation based on system requirements and architecture. Future articles will cover textual, function block/data flow, state chart, and simulation and modeling methods.
A Programmable Logic Controller, or PLC for short, is simply a special computer device used for industrial control systems. They are used in many industries such as oil refineries, manufacturing lines, conveyor systems and so on.n these modern times a PC with specially dedicated software from the PLC manufacturer is used to program a PLC. The most widely used form of programming is called ladder logic. Ladder logic uses symbols, instead of words, to emulate the real world relay logic control, which is a relic from the PLC's history.